Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSMERCURY1991COUGAR LS, 3.8 4REPAIR AND DIAGNOSIS (SINGLE PAGE)ELECTRICALSTARTERTESTINGIGNITION SWITCH CONTINUITY TEST
1991 Mercury Cougar LS, 3.8 4
Ignition Switch Continuity Test
1991 Mercury Cougar LS, 3.8 4SECTION Ignition Switch Continuity Test
NOTE:
For an "engine not cranking" condition with A/T, determine if condition exists in both Park and Neutral positions. If condition occurs in one position and not the other, a more probable cause is the neutral start switch. See appropriate TRANSMISSION SERVICING - A/T article in AUTOMATIC TRANS SERVICE section
- Test ignition switch operation by rotating cylinder/key through all switch positions. Movement should feel smooth with no sticking or binding. Cylinder/key should return from START position to RUN position without assistance. Inspect and repair if necessary.
- Remove instrument panel lower cover. Disconnect multiple connector from ignition switch. Connect a self-powered test lamp or ohmmeter between blade terminals indicated in following steps. See Fig 1 .
- Continuity between any blade and chassis ground should not exist in any switch position except proof circuits in START position. With ignition switch in ACC position, continuity should exist between terminals A-1 through B-5 only.
- With ignition switch in LOCK and OFF positions, there should not be continuity.
- With ignition switch in RUN position, continuity should exist between terminals A-1 and B-1, A-2 and B-2, A-3 and B-3, A-4 and B-4, and I-1 and B-5.
- With ignition switch in START position, continuity should exist between terminals I-1 and B-5, I-2 and B-1, STA and B-4, P-1 and GND, and P-2 and GND.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.